Axillary lymph node dissection is done in conjunction with lumpectomy or mastectomy to determine if breast cancer has spread to the adjoining lymph nodes. The conventional surgical approach leaves a surgical scar that is unattractive and can restrict range of motion in the shoulder joint. Also, squeezing and pulling the tumor during the breast operation can stimulate tumor cell metastases. A new study in the December issue of Mayo Clinic Proceedings reports that an endoscopic technique, mastoscopic axillary lymph node dissection (MALND), can reduce these complications.

1,027 patients with operable breast cancer were randomly assigned to one of two study groups. The first group underwent a breast operation and axillary lymph node dissection by conventional surgical means (CALND). The second group first underwent MALND and then conventional breast surgery. Both groups were treated post-operatively with systemic therapy and radiation therapy. The patients were followed for 63 months.

The average blood loss in the MALND group was lower than that in the CALND group. There was no significant difference between the two groups with respect to operative time. The patients who underwent MALND had less axillary pain, numbness, paresthesias and arm swelling. The aesthetic appearance of the axilla was much better in the MALND group than in the CALND group.

No statistically significant difference in disease free survival or overall survival between the two groups was observed. However, there was a significant difference between the two groups in the distant metastasis rate in favor of the MALND group. "This is the most significant finding of the study," says Dr. Luo. "While there is not as yet any significant difference in survival, longer term follow-up (e.g., 10 years and 20 years) is still needed to make a definitive conclusion. This may suggest that the axillary operation should be done before the breast operation even in conventional surgery."